External ID: ST2_IL33_Inhibitors_Primary_Screening_77700

Protocol: High-throughput screening was performed at Indiana University screening facility (Indiana University, Indianapolis, IN).

In summary, a mixture of ST2 and IL-33 was prepared by adding 0.30 microL of 14.1 microM recombinant human ST2-Fc Chimera and 0.30 microL of 55.25 biotinylated recombinant human IL-33 to 1.4 mL of assay buffer. In the HTS, each well of a 384-well Proxi-plate was first blocked by 100 microL of assay buffer for 1 h at room temperature. After removing the blocking buffer, 20 microL of ST2/IL-33 mixture was pipetted into each well and incubated at room temperature for 1 h followed by addition of compounds at 17 microM (0.8 microL) to each well and incubated at room temperature for 1 h. Ten microliters of 60 microg/mL anti-6xHis-conjugated AlphaLISA acceptor beads were added to each well and incubated at room temperature for 1 h before addition of 10 microL of 60 microg/mL of streptavidin-labeled AlphaLISA donor beads for incubation at room temperature for 30 min. Incubation of acceptor and receptor beads was conducted in darkness. The well with 3 nM ST2 alone was used as a negative control, whereas the ST2/IL-33 mixture with a human ST2 antibody added at 0.45 ng/microL was used as the positive control. Plates were read using the Envision Plate Reader. The buffer used in the assay contains 14.37 mL PBS, 30 microL Tween 20, and 600 microL of 5% bovine serum albumin in PBS.

Comment: PubChem active indicates >= 30% inhibition of ST2/IL-33 at 17 uM of the compound. Inconclusive: >=10% and < 30% inhibition.

External ID: KUHTS-Muma KU-CaM-Htt INH-01

Protocol: 1; Dispense 45 nl compounds (10 mM stocks) using ECHO 555 to Alpha 384 well assay plates. Dispense 45 nl DMSO to control columns 1 and 2 of 384 well plates.
2; Incubate 5 ul of 6XHis-mHTT (Final, 13 nM) with the compounds for 40 mins at room temperature in buffer containing 10 mM Tris.HCl pH 7.4, 1 mM calcium chloride, 150 mM sodium chloride, 0.1% BSA and 20% glycerol.
3; Dispense 5 ul of 6XGST-CaM (Final 13 nM) in buffer A.
4; Incubation; 1 hour (dark at 25C)
5; Dispense 20 ul of Nickel chelate acceptor beads (Final, 20 ugs/ml) and Glutathione donor beads (Final, 30 ugs/ml). Incubate for 2h, room temperature.
6; Detector: Perkin Elmer Enspire, Alphascreen Module (Excitation 680nm/Emission 570nm).

NOTES (numbers refer to Sequence numbers above)
1. Alphascreen bead incubations were performed in green light, TiterTek setting 400rpm.
2. All incubation and addition steps were followed by mixing and centrifugation at 400g,1 min.
3. The percent inhibition for each compound was calculated as follows:
100- [100 *((Test Compound-Median Low Control) / (Median High Control - Median Low Control))]

Where:
Test_Compound is defined as wells containing His mHTT + GST CaM in the presence of test compound

High_Control is defined as wells containing His mHTT + GST CaM and DMSO.

Low_Control is defined as wells containing His mHTT and DMSO.

Comment: All percent inhibition data reported were normalized to high and low controls on a per-plate basis. The results of primary screening data include compounds contributing to assay signal interference, interference with tags binding to Alpha beads, chelators, process related artifacts etc.. The actives were defined as compounds that inhibited Alphascreen reads to greater than 50%.